Scrying is a great way to make sure that youre putting the cards that you want in the right place, and River Song punishes your opponents who scry, surveil, or otherwise search their library
The other unique feature is that there is also a holofoil version of each of the 25 cards available, and these holofoils have a special confetti pattern, a pattern only used for special promotions such as this
It is true that a card like this can make you a target, but tribal decks often already rely on swarming the board
At GP Barcelona in 2019, during the Hogaak Summer, I was playing Hogaak against Eldrazi Tron on Day Two and my opponent opened with a Leyline of the Void and Grafdiggers Cage on turn one, on the play
Starfield Vocalist A more open-ended Panharmonicon in creature form, I expect ETB/flicker decks will be interested in Starfield Vocalist even before they consider the cheap warp cost
On the MagicTCG subreddit, someone shared a call-out for The One Ring